1. The effects on the serum electrolytes of long-term treatment with either mestranol or a placebo were determined in 175 healthy middle-aged oophorectomized women. In forty of these women the packed cell volume (PCV), serum albumin, serum and urinary osmolality, inulin space and total exchangeable sodium (Na e ) were also measured. 2. The mean serum sodium and chloride concentrations were significantly lower in the mestranol-treated women, and this was associated with a significant reduction in the mean PCV and the mean serum albumin concentration by comparison with the placebo-treated group. 3. The mean urinary osmolality was higher and the mean serum osmolality lower in the mestranol group such that there was a significant increase in the mean urine/serum osmolality ratio as compared with the placebo group. 4. The mean inulin space was significantly higher in the mestranol group as compared with the controls, but there was no significant difference in Na e . 5. These findings support the hypothesis that oestrogen-induced fluid retention is the result of primary water retention with secondary redistribution of body sodium.
1. The specific gravity and zinc concentration of plasma obtained during fasting were measured in pre- and post-menopausal women. A number of the latter had been taking 20–40 μg of mestranol daily for at least 1 year. 2. A highly significant correlation was found between plasma zinc concentration and plasma specific gravity in the oophorectomized women who were not receiving oestrogens. 3. The mean plasma zinc concentration was 2 μg/100 ml lower in the pre-menopausal women than in the oophorectomized controls, and this was wholly consistent with the associated fall in plasma specific gravity. 4. The mean plasma zinc concentration in the mestranol-treated women was 12 μg/100 ml lower than that found in the oophorectomized controls, and could not be attributed to the small associated change in plasma specific gravity. 5. It is suggested that the fall in plasma zinc concentration associated with mestranol therapy could be due to either a qualitative change in the plasma proteins or to relative zinc depletion.
1. Serum lipid concentrations were measured in groups of women who had undergone oophorectomy and hysterectomy or hysterectomy alone. Measurements were repeated in some of the oophorectomized women after treatment for 1 year with either mestranol or a placebo. 2. A significant correlation was found between serum cholesterol concentrations and age in the women with intact ovaries. Although such a correlation was not apparent in the oophorectomized women, the younger women in this group had significantly higher cholesterol concentrations than the younger women with intact ovaries. 3. A significant correlation was found between serum triglyceride concentration and age in both groups of women, but the oophorectomized women showed a significantly slower rate of increase of triglyceride with age than women with intact ovaries. 4. Administration of 20–40 μg of mestranol daily for 1 year was associated with a significant fall in serum cholesterol and a significant rise in serum triglyceride.
1. A group of women who had undergone hysterectomy and bilateral salpingooophorectomy were studied and subsequently given either 20–40 μg of mestranol per day or a placebo for 1 year. 2. The administration of mestranol to these oophorectomized women for 1 year was associated with significant falls in serum calcium and phosphorus concentrations, a fall in urinary calcium excretion and a rise in relative urinary phosphorus excretion. 3. It is suggested that these results are consistent with an increase in sensitivity to calcitonin and that the relative hyperphosphaturia reflects a compensatory rise in parathyroid hormone activity.